SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1adc3cc0531dda3c3da4d54aadd0b50685dc3ac1665b1b73881f5db3af7fdda8' 
  AND token = '38Kpqmz2XskgJa7WHxKuE5bH+uViobS1mBQ9R6i0jp8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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