SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa81f47de86e2f0b6857d289f83d4c25df4fdeafce212f65f5be67ad07a687a5' 
  AND token = 'QKcRwfjX5Z2MqBfetaOofE2H74QJXD98Z2DbW8JRj+s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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