Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f49933eeec73470b8c81e15978d13482f51d31f88d300c5230839419614c46da' 
  AND token = 'lCfkyr4z/XUOM2ayLAUYZFsxLBbtA/vAUJPaCbfYqno=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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