SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2e1660affafc0d7418f0c4750ba1e9ec358fe305c553ec30c26fc74186a7bb28' 
  AND token = 'Btc0lxT0Qh9BhrfyasOVkwGhzbErYJER2CrNBicFKbk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00084

JSON explain

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