SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be807d71674061f65917cee7efe6be6b6a1dc59d0c5c4cd083564479cd75d3d9' 
  AND token = 'La3QVfOBYkcTdND37Jk9UDh5LbWOIy0I/CUz8umI4Dg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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