SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b72a3aadfa6d512153d4eeb8347c774d6637daacfae55192da4b1666935c278e' 
  AND token = 'QqA8Erkk0kFUShHdUmLGbiHXCGKMiVtVF7ktt32sPoE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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