SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '038a500e84dc1b286fd0571ead33ada180d68df42c8fdb95b89d3db5ec71cfb7' 
  AND token = 'Lw8TCavB529V6dyRqxgMJvdp9/0uIrMuIJ7uv3EzYck=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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