SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd569e63fe37ac529d97a5f7c36af0cb10c9562da805e1778a2080556e22e3937' 
  AND token = 'xXTak/4CsZWuLGpIz+2yAK4YOMropBz+Kn53Vv/aVuE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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