SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a1375dfb151e47d981311798cb8ed09f9a93e87e2e55b88b0f02e5846d749254' 
  AND token = 'uVSfOaxenhQNeJTJ4Ch3FyRd07CawgdpBzlS6CuLYrs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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