Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fc690d20d2f07440afdf04d735acbe779c213f237c8479a3beddb2fa7f8f9a83' 
  AND token = 'D6RNIQCybfZAxEcRdxoCsIc+46WdTJ7HR3jiA6yczj4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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