SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '822fa4b59637b685d52359093d984efa3464bbb915067034bd4a89a1f94fa794' 
  AND token = 'WQvt7b77WkRXin3tLA/afqzsKolH+MlWeHDTreVL+qE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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