SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '968bf19326d2d8e782d88b69aae61155a0eeff5cdcd1f81a9e84fc095aba492b' 
  AND token = '+nyudTkHHEwTHw9PHZuu1m8UQzqx5KFM5t/lcjGWtVU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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