SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6cbfed55e1200f72dae67195531aad45fc5048a2a0239fe18e72fb533f38ed3e' 
  AND token = 'f2DolnGdUik0PksEYoZzROGLlYNuM8tv7G1oK8tQ8vc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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