SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae7aa3f0416605b2d57c255487774ded0e360f25f0899bfb6022169eaeaea1cb' 
  AND token = 'bP0dN3qvMXNWV7WVbErsNs4cXWS22zsDiR1simpCosQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}