SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1f87329ddb6dc9f102b79fb4c87f4c7702031d0dad57d0a04e08b2fbf3df6a1' 
  AND token = 'AbZ8gtlK7BnQ+b4Axxxd/ibIlgPIEwvIN92Xc15F44E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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