SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '213cfd7a5da78f1346c5b99d8d5e46ab8461cd62dc4b25828eb9d37650bad9f0' 
  AND token = '4TJXiF7K1NDX1kZ+nk0z08Zcy3pYqt/ylZGS3I54MXQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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