SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bbf629e116f2eef3691ce4f59b13a68ca053635ccae30733dc33b1da7bb9cfd3' 
  AND token = 'gasYhfFEJGvz+qpwfvPee4VAhDk9vgW1IN+sBf2Ei6M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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