SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '389b93e791fc8b70b50acefce7ea599bda246eacc03d56dfc8e073c408d07484' 
  AND token = 'HShVklWimVzW/V65ffLulGjk01mK3Y4ov9ORJLPOJB0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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