SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33e23a51ad8429ae7a038097515c9846d22f2d466e9412f40b7cf11df54b3822' 
  AND token = '4g6zRyx5wmvpiYnl864JEIlR7Vn/1v67VZ17mNu7O1A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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