SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '34163fd4894ae85d7298d3247599908a642c391a54b4cb41ad4fe75b91d3d519' 
  AND token = 'ww9G25mNlWqnR4u5rCiBNOONSb9O749DxBEgVqBcoC8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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