SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '43fb740609d5220c5cd35ad917abddc705bff3abf16685a3ab8aabe94331bd09' 
  AND token = 'QPwvG00+tNmyxCf5DQP19Hsg/g6nslatIe12ZoJri10=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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