SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd4fff2370b159b20da39a4c1cc80800b73f41bb3729463287cec0bb4f3072407' 
  AND token = 'qlQWNYAU6nY+4UKWgSF2OA44N/EVeS6NL9B4MkQAFc4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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