SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '75e9a8b5c58126f391d11dbbb5b597b1a12e1cbf2521fb6a14f7b22b88e4e1de' 
  AND token = 'cWRuEgjBQNJyRg5jDFxv0ilINF5XqO6BEu6c78tPxBI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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