SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b054c6c25d3b19f7950a21d4cc6782957f5d5536e4e30bd2b9de93e8f68d5583' 
  AND token = 'pBY+Jt8qVb3WhBhSgDqfb+GAnBTrSR45IZSuGvFUe9g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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