SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '199ef1b6ccfd232c51d2efcdd177a40d5160509c36605229197366d7c37f35fd' 
  AND token = 'P/OTPn8VWHgW5pKZ/nxcCZqJUHZq0RHUCqWyRJ82Yz4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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