SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eda3b7a62534a46202580f798a7e8b3d20dbda9089b994bb692bb00bdcedaa47' 
  AND token = 'gPAMDYlbBAbPJoAy1TtdKuVug8HmSnYjEyCYYQk6U2A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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