SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3fd39466cf2afef55c6e0bd6613fc89c289a96015451c0c88b2f3524ca412239' 
  AND token = '1zAoJPMoR/dWWdWmDwI/zWZTyF+Iy96oUnZmfTDlZgk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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