SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '36d1fbb295a1ecd1c5696963ef7fedd03374051b830c3c8c1088834407797b5a' 
  AND token = 'Z9qkv6KhzQ6BleYzqytw1cC7pvx6rdZHYKmYvSgdA3E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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