SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9c1af3ca819233424ff727bed62e05b41d441ce16dd8ac9129e83b8d36b12f23' 
  AND token = 'hOoZaTETwZ37gMV5FTMbZz0tpinaLXhGMf9LX6obiTA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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