SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf2bcd1cf1baacf0ede13ba77998642800474e58fe33f291264ded56a2d33b5b' 
  AND token = 'gNT/zidsIDNytuuLiyHYhYIY4te4HWs7o6vp4Q6Ukqc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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