SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '970754e01060b926cd9986628025e0339f68e83a1b2a18feeb69f1b7b77927e7' 
  AND token = '5K0Xpds8uw6FqVfO/P+aS+rqyBTNiNx0EZ3CIzSbIqA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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