SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa11f830f77ff06e115b312e5f27e7dcbb648d222f4bc09806b88e6dba31f538' 
  AND token = 's+r/ATeJbiFhqZvcIHO5/mpneHYh6YkDHs/BXUQ9tyY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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