SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e698150f606278848ba27a582c553367001a389733ad7fd497b7a9a1f5b13065' 
  AND token = 'NXrBY/DfRNa4iK2hw81oChTHmIHjdxqQxj/6nSsP5XM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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