SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8e34c5228af8de1009572241877638d50624c12e9fb03a4f059f92379883b663' 
  AND token = 'wf0goVwqydOp7eJKfOf/EP7fSL7V7ZSganowGfZWHvE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}