SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf5d964385016eb6693f6aee48f56fc8911858a2a2bee97b4c355bf5b9e1afb1' 
  AND token = 'dwqLHDC4rZ41DZ/CBQUkCrO2mz9SHScI+9ilkZGtHvM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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