SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'efb3100667e57b253ce7730fba19d76fec3cd5522a0df61c9177841ae66a5ec9' 
  AND token = 'pioJvadIkdvG4vqYgp0xmKgDbOoz384l9wQemyuMvXg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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