SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fdcb96bca50d4e678250fd9cd7c26433bf2985705bf6ec116ed95f01d674fcb7' 
  AND token = 'w7tg32e5rSGwePtDYVYrr2RguAVmsVq6AiOwMNMTzhA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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