SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5af54d70992e505adc50363953349ae29c3a583eb13873dd9a65d7a9a240801f' 
  AND token = '3EyHavj9uKcLsVQKtnEGSy1VjSYcCQqlezhlc67Vcyw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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