SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '01239bf2fd326855c6c5a8f1414e2aa2b83c3412ec30ec6c14a596f95536a591' 
  AND token = 'NP9MocxuhR+kUgllivD6Qyhk7O8nuQ4iOSm6wjFMWz8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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