SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '00557a529150299bbeecb4f1429f77d5888eb1024f26d636234b957c1182e83d' 
  AND token = 'AFu88mTsE5u4AYuCDFeuekVYECSVzQF6P/5VFHhsAZA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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