SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3dad1a129da7c8147bb2790228f3a895f8bccec2eb192e01ba4613138843d9ec' 
  AND token = 'fkwArzMh0vYgx2+jPPDzUrR3MZF1V1bv0Ey8G4HX3W8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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