SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '76bc88ca0e23817c3828c59319f92526877b5d96390ae0c1ba96fde6a4f533d7' 
  AND token = '7MZ/6ZYpou0DPpwX/23Es1i9Xqa+SYJm8N7RroF1Psc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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