SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a46bd8b08b10659e84d31f447fa6671116dcc217c45d4a95a4d71db0bca976f8' 
  AND token = '3JMRZmyIivYPRzZyYd41d/rBV9tu6Nt0qw60QRX6lj8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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