SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '4eaf145cdd42050f1387ac21b32ef380cd89cd99f1bf228d711a724fe05ca26b' 
  AND token = 'HVL+5PhXNRpCvfifhtJr935WAuyYlFR6LKg5V03x2lM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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