SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9b27627727e9c16fbbceef49501231fd49473c2db576afade750c059e2cc5669' 
  AND token = 'TBownro30Y43LqbY3lEVCaRYM5mkdfyVedJ25F4FSAc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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