SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b5f3c289c49589228f57e89c452fa906827e2a4ddbe17246d579e34ccfbbeda5' 
  AND token = 'g8o0IvtXqLu1OkJctJKmxVF1ZpTO0V0UX5qloCrHSzI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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