SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a96be5ed81f35e263e580fab4973696b6d826aca5ccf32f767434d47049cd24' 
  AND token = 'RkdLrOIBHyK1BjE/m4KMh5K3EwpSqaKI7uFhYzRWKQA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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