SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd9343a64446dcae701322b8581c00abec4bf27b0cc9c85c58ec55d9b79f06e4' 
  AND token = '0AjfEwOTyOuDmeFbUjMKbU3o++3E88hMqpKIsuhMBV0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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