SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '85bed46c58071f8be2e71438f51cf353c463002db70102f0572aef419479a44e' 
  AND token = '1oR1nPKfJbtKABS159uVZI59Q2lIK7stuOKqFWXtdxo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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