SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '12056cf322c1894d6d52fad94a43e436dc92e5ec42e71e8eafad2447237611df' 
  AND token = 'JmZYYkMdqQCiHt3frrgYftMj4G1iFqfLRu/tvYi9CHQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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