SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a53563129dda80fc648aebf744e37a51a14a4459599553d6b8a2c141a51551d' 
  AND token = '0CpqGAevsN6l6kHuB2iKouHSFU/OJk8gfDl6y8YB76Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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