SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f754823ce8429b7cfb222cd5c89d03898c4b0628218f05fa23088d48134b1ea' 
  AND token = 'h8bVHPHdEtPoupp/MBz8Zr88myImzdDWFg6UhHw6ZnA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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