SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aeac83cd046c071f6ec52af58a4521bd26479d8930d8fdcc85e3c32662c8fdd4' 
  AND token = 'R/iaModpL9cJCQM2+7nQ9h0c3uQrEsPuMU6jMLFT8vg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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