SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '53ab84281eb3d3f44d110ab929a7cf57ec55302ffc20d50029732ef5fd969c34' 
  AND token = 'WHWIAVoMkRSON7Xs1vkOyZoopZjF9XlIy00yVqHQ86Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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