SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '177be368ffa45548821eec2d8520f7c7fbc461e210bdde66cf9d982bde0e3943' 
  AND token = 'WYbP4eIK7mL4VkowwHcUbGkqmF7TcgZYUP+UJ0ZlQ/4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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