SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae2aa92794cd0b1d7ef94fba0f94d04861f78b95ba901ce128d76bbcdf366887' 
  AND token = '3rZe4gtKcKYuGU7jvB8QLrKUX/Gr/FTIoR+Y/Xsm1R4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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