SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e7a786bc21370cd7fefeaa962bcbeea51d32ae5b4d457d28afd3b983ef36942f' 
  AND token = 'GVE9yNTjZF1oB/+E2GTWq14o0bmVRdB0lkb1LukGH2M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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