SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c3c3897e0b96881366a4a46f55adc467af54c7b5494d99d39590ff460a6f5940' 
  AND token = 'jrXqjyirFuHdnfNzgndg8bMSwlu3D/9oFULlLQW+AHc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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