SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd106f18a550fe48d63d01a43eb79038fd9ceca692cff04b81902196ab248287' 
  AND token = 'T/YZHSqacfTk6QQTXTy95xpGyauzbbgJKR1yXcK7Bkg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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