SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a1b02126196c741749f5af07b0a06d98864bfdd3b64da06034629ccc23fa046' 
  AND token = 'CCYX25PWB77ma7WOglaGOSrbV8tEyhDt5Cx/lQxA89A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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