SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9e7956c8419ab2f475d9ca1d9e49dd67a2eb304c2c4c094cf3f9988181d4a206' 
  AND token = 'vISjKF4Q9nipV9JNvgwRuGW7knIiqxezYYOJCgHJ+IQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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