SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f2ab20abf1ff2fcad45ddccdda465447f0348aa79fb9b864175c6648732137d2' 
  AND token = 'ZkI0yceWyQDjJbequweh+NXvsKP8P3Nl1ZDnCspXM4M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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