SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd1726c9ec53b7e1a0adda2b81708b5761920587637adc8c92701551507986501' 
  AND token = 'f1wRjTqgSSkW3ERhWmAB2rAeZN8GzsbW722EgWsIQ4c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}