SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5238cf61dc879d3b59342b0b4c95b6082ad34911b20d0375435b54e9b26f33ff' 
  AND token = 'H6elQvttiiYwXCVf3brui5tUk0CBcLydV4Kr9/0hZg8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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