SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '194bc886e74257a91faf8f39ce992b0e7a95149c88a4b254d5fc564903614a53' 
  AND token = '7IQgF+Ik9KIbIXCNEcJuKUphMisDjHDGTJ/3JAXuQFg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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