SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '084da4a9a7b521b17f9c153f8506197d0cf58d01edb0f072f99326d67b0dd224' 
  AND token = 'KPMyYK6N4KB0ZiUc45ya1ya7hCHJrKgOGWVPo63RSis=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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