SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fc778090a2d692354dfdf0733380baa620db6566dac0e0cad9236dc12d7a39fb' 
  AND token = 'siswYOkjhgnlA4til4A7pvETF0WjF/58/nTBGL7HVqo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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