SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'deb7ee611f175d055417736aed41ae32f3c9174ff331b2bcf91804b7a918ac24' 
  AND token = 'NEcyK6p83lZFyOQtwJDtGeTiEAXtjyzJMh8vUqFoT8o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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