SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf7dd829d81833e5b29a220f3e2ad8d877bfe56cd7f11246079db830e7bcfb5c' 
  AND token = 'ITmczUjK/vijJpBbMd7i28idl6fG4WPYeVAQWb0vO5I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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