SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5bdb904cd912389fc3685e303a8facffdd5098ae582cfbdd0c2aec8941038b3d' 
  AND token = 'GN+ySRNStV1rr+S1bbu+CkerydoOpOXTLTjeBoym8kY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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