SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '23a9c36ff792f00019e4c4a54cea6541b4ef97d78399d4874497e22fa6dd4835' 
  AND token = 'S9jVZYxllU5+ZYrVf2OxSojMZHwueB6gDimAGkdww+Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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