SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '5e5b487862c982b28ee160d770953108afb08406046005db5d27134968e195bf' 
  AND token = 'OXJ+B+3o++t6YjJE2l7+pVgkTxXAspU+yy2F/E7Tq7Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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