SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '30b4009edc8c51d1b46093c0f9a35aa538d35b05b2e8c25c50db67dfa5e49119' 
  AND token = 'plyChWCFtIAXo428HH7NizEBifuhgY70JnnI0/fNSZw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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