SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '27fb5ff62cbd694c378ec748c6e615df9350a6d0b6eb8e51bbb6133a9db2bb2b' 
  AND token = 'mSAEdJDCbIYRPJj7Nt1F0VtKUUmBTQVcuvRKToa7ess=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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