SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e87351a481ebfc64ca9b688ddb2e9444a2d464df2ccbb040a55f5726bce22e6f' 
  AND token = 'JjNJDe8/ahnebQQGWKz05uMgBtWJWDdKvRhKfegmadI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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