SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72235cda3dc5d09aed9e59d2fbb278a01531de5c26778539990a505c9220a2fc' 
  AND token = 'rQLkbKm3/TiUdnrhIHCWwob+QhYyJWMsXy9AZtA/wCE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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